Adds the ability to validate two fields at the same time. For an intermediate table with many-to-many association
Add to your Gemfile:
gem 'dynamic_uniqueness_validator'And then execute:
$ bundle install
Add inverse_of to model with has_many. Then add the following to your model:
$ validates :my_model_item, dynamic_uniqueness: { parent_association: :parent_model, child_association: :model_item }
You can also use the message option
$ validates :my_model_item, dynamic_uniqueness: { parent_association: :parent_model, child_association: :model_item, message: "Custom error message" }
The gem is available as open source under the terms of the MIT License.